Variación longitudinal de la anatomía y de las propiedades físico-mecánicas de Centrolobium yavizanum Pittier. proveniente del Guaviare, Colombia

Abstract

The present study evaluated the longitudinal variation of the anatomical characteristics and physical-mechanical properties of Centrolobium yavizanum Pittier, from a forest plantation established in the department of Guaviare in Colombia, establishing the potential uses of the species in different sections of the stem. Three individuals located in the experimental station El Trueno of the SINCHI Research Institute were selected. For the study of the anatomy, biometry and physical and mechanical properties of the wood, samples were taken in the basal section of the trunk (X), middle section (Y) and apical section of the trunk (XY). The tests were carried out at the Wood Laboratory of the Universidad Distrital Francisco José de Caldas, in Bogotá, using the methodologies and standards established for each of the procedures. Thus, the procedures registered by IAWA and by the Technical Norms for physical-mechanical wood testing (ASTM, COPANT, NTC) were used. It was found that the wood of C. yavizanum presents a diffuse porosity, solitary pores with contents and no arrangement pattern. Its rings are defined by latewood banding. The intervessel pits are polygonal areolated intervessel pits and the vs-ray pits are similar to the intervessel pits, while the fibers presented simple pits. Regarding the biometric study, it was found that the fiber length (Lf) presented a mean value of 517,633 µ, decreasing its value from the basal section towards the apical section. The pore density (Dp) presented a mean value of 10.9 pores/mm2, the fiber thickness (Ef), registered a mean value of 2.098 µ increasing its value from the basal section towards the apical section. This wood had an anhydrous density (Da) of 0.638 g/cm3, basic density (Db) of 0.539 g/cm3, a fiber saturation point moisture content (CHPSF) of 22.59% and a coefficient of dimensional stability (CED) of 2.6. Its longitudinal variation in physical properties was only in the CHPSF. In terms of mechanical properties, the species reported a mean value in static bending (RM) of 938.39 kg/cm2, in parallel compression (RM) of 502.23 kg/cm2, and a mean value in shear stress (EUM) of 160.135 kg/cm2. Its longitudinal variation occurred in the mechanical properties of parallel compression, static bending and shear. Significant correlations were found between fiber wall thickness with basic density and anhydrous density. It was determined that the most suitable uses for the species are interior finishes, joinery, carpentry, structural wood (sleepers, beams), flooring, formwork, handicrafts, plywood, packaging, agricultural implements, toys and molded products. It is a species of high commercial value.